This chapter presents the fundamentals behind selected experimental techniques used to control and monitor some coupled multi-physics processes. The starting point is the review of the experimental techniques for coupled hydro-mechanical testing (liquid and vapour transfer techniques). Then, fundamentals of physical processes related to electrical techniques for the characterisation of geomaterials and for the induction of coupled electro-chemo-hydraulic processes are provided. Complementary aspects concerning the application of these techniques and some of their limitations are also discussed. Selected data from tests on a clayey silt in an electrokinetic oedometer are finally shown, to provide evidence of some effects of the coupled electro-chemo-hydraulic response of soils.